Preparation of di-ethers of tetraethylene glycol



ethylene glycol of the UNITED STATES PATENT. OFF-ICE I PREPARATION OF DI-ETHERS 0F TETRA- ETHYLENE GLYCOL Glenn F zellhoefer, Bloomington, llll. No Drawing. Application August l2, 1935, Serial 8 Claims.

The present invention relates to the manufacture'of the symmetrical di-ethers of tetraillustrative general formula:

where R is an alkyl radical. such as methyl, ethyl, etc.

The object of this invention is to converta mono-R-ether of ethylene glycol into an alkali metal ,8 alkoxyethoxide, and then to displace the alkali metal from two molecules of the alkali metal 3 alkoxyethoxide with a di-halogen derivative of diethyl ether of the general formula (X--CH2-CH2)2O, wherein Xv is a halogen from the group, chlorine, bromine, and iodine.

The invention may be carried out as hereinafter illustrated by reference specifically to B being the ethyl radical, to sodium as the alkali.

metal, and to 5,,8'dichlorodiethyl ether as the dihalogen diethyl ether.

Dry ethyl ether of ethylene glycol:

CHsCHzOCHzCHzOH is stirred and refluxed with a measured quantity of sodium in amount insufficient to react with all the said ethyl ether of ethylene glycol whereby the excess of said ethyl ether of ethylene glycol remains in process as a vehicle or solvent for the other materials.

By excluding moisture from access to the liquid being refluxed, all of thelsodium will react by replacing hydrogen in the glycol ether to form Thereafter afidichlorodiethyl ether is added in the amount to provide suilicient chlorine for all thesodium for the formation of sodium chloride. In adding the 5,;8dichlorodiethyl,ether, the rate of addition is such as'to control the rate of reaction. After addition of the fifi'dichlorodiethyl ether, the material is maintained at a temperature-of to C. and stirred for approximately forty-eight hours. The liquid is then cooled, filtered and distilled. The fraction boiling at 132 to 134 C. at 4 mm. pressure (or at about 502 to 507 F. at atmospheric pressure) is diethyl ether of tetraethylene glycol:

C2HsO(CH2) 2O (CH2) :0 (CH2) 2O (CH2) iOCaHa eases (oi. 26li-l5l) The dimethyl ether of tetraethylene glycol is made 'in the same way using initially the methyl ether of ethylene glycol.

For the end product with the radical B, it is necessary only to use the R-ether of ethylene glycol. The sodium and the chlorine unite to form sodium chloride, and the specific selection of sodium and chlorine is only a practical means to the end of uniting two molecules containing the alkali metal by the connecting link derived from the di-halogen diethyl ether. The ,8 alkoxyethoxide molecules at their alkali metal linkage become attached to' the halogen-containing molecule at the two halogen linkages.

The di-ethers of tetraethylene glycol of this invention are stable compounds, having g neral utility especially as solvents and plasticizers. Where R is methyl or ethyl, the dimethyl or diethyl ethers of tetraethylene glycol are excellent solvents or absorbents for refrigerants such as dichloromonofiuoromethanc, methyl chloride, methylene chloride and ethyl chloride.

In the accompanying claims, the process of iii manufacturing the materials is set forth-in terms I 3. The process of claim 1 wherein said mono alkyl ether of ethylene glycol is the ethyl ether thereof.

4. The process of claim 1 wherein said alkali metal is sodium.

5. Tetra ethylene glycol dialkyl ether.

6. Tetra ethylene glycol diethyl ether.

7. Tetra ethylene glycol dimethyl ether.

4 8. The process of producing dialkyl ethers of tetraethylene glycol, which comprises convert-v ing a mono-alkyl ether of ethylene. glycol to the alkali metal derivative, andheating said alkali metal derivative with 13,8 dihalodiethyl ether, to split out an alkali metal halide and produce a tetraethylene glycol dialkyl ether.

' GLENN-F." ZELLHOEFER. 

